Radiation Therapy for Prostate Cancer

Abstract

Annually, there are nearly 3000 new cases and 500 deaths from prostate cancer in Missouri. When treatment is appropriate and necessary, radiotherapy offers similar cure rates to prostatectomy, with fewer long-term sexual side effects and little effect on urinary continence. Radiotherapy is delivered with external beam or implanted radioactive sources (brachytherapy). In high-risk disease, combinations of external beam and brachytherapy offers improved biochemical control. Following prostatectomy, salvage radiotherapy should be initiated as soon as possible.

Figure 1

(a) Axial CT slice showing conformality of intensity modulated radiation therapy. Radio-opaque markers are apparent in the anterior aspect of the prostate gland. (b) Axial CT slice showing conformality of proton beam radiation therapy in the same patient as panel a. More sparing of the anterior-lateral rectal wall and less dose to peripheral tissues is apparent.

Figure 2

HDR implant dose distribution, allow demonstrating HDR sparing the urethra.

Figure 3

Prostate MRI (T2 sequence) before (a) and after (b) hydrogel injection. The rectum touches the prostate on the pre-injection MRI but is displaced away from the prostate by the T2 bright spacer (black arrow). This added space results in significantly less radiation dose to the adjacent rectum.